51
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Cha TY, Yong Y, Park H, Yun HJ, Jeon W, Ahn JO, Choi KY. Biosynthesis of C12 Fatty Alcohols by Whole Cell Biotransformation of C12 Derivatives Using Escherichia coli Two-cell Systems Expressing CAR and ADH. BIOTECHNOL BIOPROC E 2021. [DOI: 10.1007/s12257-020-0239-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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52
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Yunus IS, Wang Z, Sattayawat P, Muller J, Zemichael FW, Hellgardt K, Jones PR. Improved Bioproduction of 1-Octanol Using Engineered Synechocystis sp. PCC 6803. ACS Synth Biol 2021; 10:1417-1428. [PMID: 34003632 DOI: 10.1021/acssynbio.1c00029] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1-Octanol has gained interest as a chemical precursor for both high and low value commodities including fuel, solvents, surfactants, and fragrances. By harnessing the power from sunlight and CO2 as carbon source, cyanobacteria has recently been engineered for renewable production of 1-octanol. The productivity, however, remained low. In the present work, we report efforts to further improve the 1-octanol productivity. Different N-terminal truncations were evaluated on three thioesterases from different plant species, resulting in several candidate thioesterases with improved activity and selectivity toward octanoyl-ACP. The structure/function trials suggest that current knowledge and/or state-of-the art computational tools are insufficient to determine the most appropriate cleavage site for thioesterases in Synechocystis. Additionally, by tuning the inducer concentration and light intensity, we further improved the 1-octanol productivity, reaching up to 35% (w/w) carbon partitioning and a titer of 526 ± 5 mg/L 1-octanol in 12 days. Long-term cultivation experiments demonstrated that the improved strain can be stably maintained for at least 30 days and/or over ten times serial dilution. Surprisingly, the improved strain was genetically stable in contrast to earlier strains having lower productivity (and hence a reduced chance of reaching toxic product concentrations). Altogether, improved enzymes and environmental conditions (e.g., inducer concentration and light intensity) substantially increased the 1-octanol productivity. When cultured under continuous conditions, the bioproduction system reached an accumulative titer of >3.5 g/L 1-octanol over close to 180 days.
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Affiliation(s)
- Ian Sofian Yunus
- Department of Life Sciences, Imperial College London, SW7 2AZ London, United Kingdom
| | - Zhixuan Wang
- Department of Chemical Engineering, Imperial College London, SW7 2AZ London, United Kingdom
| | - Pachara Sattayawat
- Department of Life Sciences, Imperial College London, SW7 2AZ London, United Kingdom
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Jonathan Muller
- Department of Life Sciences, Imperial College London, SW7 2AZ London, United Kingdom
| | - Fessehaye W. Zemichael
- Department of Chemical Engineering, Imperial College London, SW7 2AZ London, United Kingdom
| | - Klaus Hellgardt
- Department of Chemical Engineering, Imperial College London, SW7 2AZ London, United Kingdom
| | - Patrik R. Jones
- Department of Life Sciences, Imperial College London, SW7 2AZ London, United Kingdom
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53
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Weber D, Patsch D, Neumann A, Winkler M, Rother D. Production of the Carboxylate Reductase from Nocardia otitidiscaviarum in a Soluble, Active Form for in vitro Applications. Chembiochem 2021; 22:1823-1832. [PMID: 33527702 PMCID: PMC8251736 DOI: 10.1002/cbic.202000846] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/28/2021] [Indexed: 01/22/2023]
Abstract
Accessing aldehydes from carboxylate moieties is often a challenging task. In this regard, carboxylate reductases (CARs) are promising catalysts provided by nature that are able to accomplish this task in just one step, avoiding over-reduction to the alcohol product. However, the heterologous expression of CARs can be quite difficult due to the excessive formation of insoluble protein, thus hindering further characterization and application of the enzyme. Here, the heterologous production of the carboxylate reductase from Nocardia otitidiscaviarum (NoCAR) was optimized by a combination of i) optimized cultivation conditions, ii) post-translational modification with a phosphopantetheinyl transferase and iii) selection of an appropriate expression strain. Especially, the selection of Escherichia coli tuner cells as host had a strong effect on the final 110-fold increase in the specific activity of NoCAR. This highly active NoCAR was used to reduce sodium benzoate to benzaldehyde, and it was successfully assembled with an in vitro regeneration of ATP and NADPH, being capable of reducing about 30 mM sodium benzoate with high selectivity in only 2 h of reaction.
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Affiliation(s)
- Douglas Weber
- Institute of Bio- and Geosciences (IBG-1)Biotechnology Forschungszentrum Jülich GmbHLeo-Brandt-Str. 152425JülichGermany
- Aachen Biology and Biotechnology (ABBt)RWTH Aachen UniversityWorringer Weg 152074AachenGermany
| | - David Patsch
- Institute of Bio- and Geosciences (IBG-1)Biotechnology Forschungszentrum Jülich GmbHLeo-Brandt-Str. 152425JülichGermany
| | - Annika Neumann
- Institute of Bio- and Geosciences (IBG-1)Biotechnology Forschungszentrum Jülich GmbHLeo-Brandt-Str. 152425JülichGermany
| | - Margit Winkler
- acib-Austrian Centre of Industrial BiotechnologyPetersgasse148010GrazAustria
- Institute of MolecularBiotechnology, Graz University of TechnologyPetersgasse148010GrazAustria
| | - Dörte Rother
- Institute of Bio- and Geosciences (IBG-1)Biotechnology Forschungszentrum Jülich GmbHLeo-Brandt-Str. 152425JülichGermany
- Aachen Biology and Biotechnology (ABBt)RWTH Aachen UniversityWorringer Weg 152074AachenGermany
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54
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Sharma A, Yazdani SS. Microbial engineering to produce fatty alcohols and alkanes. J Ind Microbiol Biotechnol 2021; 48:6169711. [PMID: 33713132 DOI: 10.1093/jimb/kuab011] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/18/2020] [Indexed: 11/14/2022]
Abstract
Owing to their high energy density and composition, fatty acid-derived chemicals possess a wide range of applications such as biofuels, biomaterials, and other biochemical, and as a consequence, the global annual demand for products has surpassed 2 million tons. With the exhausting petroleum reservoirs and emerging environmental concerns on using petroleum feedstock, it has become indispensable to shift to a renewable-based industry. With the advancement in the field of synthetic biology and metabolic engineering, the use of microbes as factories for the production of fatty acid-derived chemicals is becoming a promising alternative approach for the production of these derivatives. Numerous metabolic approaches have been developed for conditioning the microbes to improve existing or develop new methodologies capable of efficient oleochemical production. However, there still exist several limitations that need to be addressed for the commercial viability of the microbial cell factory production. Though substantial advancement has been made toward successfully producing these fatty acids derived chemicals, a considerable amount of work needs to be done for improving the titers. In the present review, we aim to address the roadblocks impeding the heterologous production, the engineering pathway strategies implemented across the range of microbes in a detailed manner, and the commercial readiness of these molecules of immense application.
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Affiliation(s)
- Ashima Sharma
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.,DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.,DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
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55
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Pongpamorn P, Kiattisewee C, Kittipanukul N, Jaroensuk J, Trisrivirat D, Maenpuen S, Chaiyen P. Carboxylic Acid Reductase Can Catalyze Ester Synthesis in Aqueous Environments. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013962] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Pornkanok Pongpamorn
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
- National Science and Technology Development Agency (NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang Pathum Thani 12120 Thailand
| | - Cholpisit Kiattisewee
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
| | - Narongyot Kittipanukul
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
| | - Juthamas Jaroensuk
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
| | - Duangthip Trisrivirat
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
| | - Somchart Maenpuen
- Department of Biochemistry Faculty of Science Burapha University Chonburi 20131 Thailand
| | - Pimchai Chaiyen
- School of Biomolecular Science and Engineering Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley Rayong 21210 Thailand
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56
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Pongpamorn P, Kiattisewee C, Kittipanukul N, Jaroensuk J, Trisrivirat D, Maenpuen S, Chaiyen P. Carboxylic Acid Reductase Can Catalyze Ester Synthesis in Aqueous Environments. Angew Chem Int Ed Engl 2021; 60:5749-5753. [PMID: 33247515 DOI: 10.1002/anie.202013962] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Indexed: 11/06/2022]
Abstract
Most of the well-known enzymes catalyzing esterification require the minimization of water or activated substrates for activity. This work reports a new reaction catalyzed by carboxylic acid reductase (CAR), an enzyme known to transform a broad spectrum of carboxylic acids into aldehydes, with the use of ATP, Mg2+ , and NADPH as co-substrates. When NADPH was replaced by a nucleophilic alcohol, CAR from Mycobacterium marinum can catalyze esterification under aqueous conditions at room temperature. Addition of imidazole, especially at pH 10.0, significantly enhanced ester production. In comparison to other esterification enzymes such as acyltransferase and lipase, CAR gave higher esterification yields in direct esterification under aqueous conditions. The scalability of CAR catalyzed esterification was demonstrated for the synthesis of cinoxate, an active ingredient in sunscreen. The CAR esterification offers a new method for green esterification under high water content conditions.
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Affiliation(s)
- Pornkanok Pongpamorn
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand.,National Science and Technology Development Agency (NSTDA), 111 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani, 12120, Thailand
| | - Cholpisit Kiattisewee
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
| | - Narongyot Kittipanukul
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
| | - Juthamas Jaroensuk
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
| | - Duangthip Trisrivirat
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
| | - Somchart Maenpuen
- Department of Biochemistry, Faculty of Science, Burapha University, Chonburi, 20131, Thailand
| | - Pimchai Chaiyen
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
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57
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Hollmann F, Opperman DJ, Paul CE. Biocatalytic Reduction Reactions from a Chemist's Perspective. Angew Chem Int Ed Engl 2021; 60:5644-5665. [PMID: 32330347 PMCID: PMC7983917 DOI: 10.1002/anie.202001876] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Indexed: 11/09/2022]
Abstract
Reductions play a key role in organic synthesis, producing chiral products with new functionalities. Enzymes can catalyse such reactions with exquisite stereo-, regio- and chemoselectivity, leading the way to alternative shorter classical synthetic routes towards not only high-added-value compounds but also bulk chemicals. In this review we describe the synthetic state-of-the-art and potential of enzymes that catalyse reductions, ranging from carbonyl, enone and aromatic reductions to reductive aminations.
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Affiliation(s)
- Frank Hollmann
- Department of BiotechnologyDelft University of TechnologyVan der Maasweg 92629 HZDelftThe Netherlands
- Department of BiotechnologyUniversity of the Free State205 Nelson Mandela DriveBloemfontein9300South Africa
| | - Diederik J. Opperman
- Department of BiotechnologyUniversity of the Free State205 Nelson Mandela DriveBloemfontein9300South Africa
| | - Caroline E. Paul
- Department of BiotechnologyDelft University of TechnologyVan der Maasweg 92629 HZDelftThe Netherlands
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58
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Liu Y, Cruz-Morales P, Zargar A, Belcher MS, Pang B, Englund E, Dan Q, Yin K, Keasling JD. Biofuels for a sustainable future. Cell 2021; 184:1636-1647. [PMID: 33639085 DOI: 10.1016/j.cell.2021.01.052] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/16/2021] [Accepted: 01/27/2021] [Indexed: 12/26/2022]
Abstract
Rapid increases of energy consumption and human dependency on fossil fuels have led to the accumulation of greenhouse gases and consequently, climate change. As such, major efforts have been taken to develop, test, and adopt clean renewable fuel alternatives. Production of bioethanol and biodiesel from crops is well developed, while other feedstock resources and processes have also shown high potential to provide efficient and cost-effective alternatives, such as landfill and plastic waste conversion, algal photosynthesis, as well as electrochemical carbon fixation. In addition, the downstream microbial fermentation can be further engineered to not only increase the product yield but also expand the chemical space of biofuels through the rational design and fine-tuning of biosynthetic pathways toward the realization of "designer fuels" and diverse future applications.
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Affiliation(s)
- Yuzhong Liu
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Pablo Cruz-Morales
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Amin Zargar
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Michael S Belcher
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Bo Pang
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Elias Englund
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Qingyun Dan
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA
| | - Kevin Yin
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Jay D Keasling
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, USA; Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA; Departments of Chemical and Biomolecular Engineering and of Bioengineering, University of California, Berkeley, Berkeley, CA, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University Denmark, Horsholm, Denmark; Center for Synthetic Biochemistry, Shenzhen Institutes for Advanced Technologies, Shenzhen, China.
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59
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Sarak S, Sung S, Jeon H, Patil MD, Khobragade TP, Pagar AD, Dawson PE, Yun H. An Integrated Cofactor/Co-Product Recycling Cascade for the Biosynthesis of Nylon Monomers from Cycloalkylamines. Angew Chem Int Ed Engl 2021; 60:3481-3486. [PMID: 33140477 DOI: 10.1002/anie.202012658] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Indexed: 11/10/2022]
Abstract
We report a highly atom-efficient integrated cofactor/co-product recycling cascade employing cycloalkylamines as multifaceted starting materials for the synthesis of nylon building blocks. Reactions using E. coli whole cells as well as purified enzymes produced excellent conversions ranging from >80 and 95 % into desired ω-amino acids, respectively with varying substrate concentrations. The applicability of this tandem biocatalytic cascade was demonstrated to produce the corresponding lactams by employing engineered biocatalysts. For instance, ϵ-caprolactam, a valuable polymer building block was synthesized with 75 % conversion from 10 mM cyclohexylamine by employing whole-cell biocatalysts. This cascade could be an alternative for bio-based production of ω-amino acids and corresponding lactam compounds.
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Affiliation(s)
- Sharad Sarak
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Sihyong Sung
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Hyunwoo Jeon
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Mahesh D Patil
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Taresh P Khobragade
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Amol D Pagar
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
| | - Philip E Dawson
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Hyungdon Yun
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 050-29, South Korea
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60
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Schwarz A, Hecko S, Rudroff F, Kohrt JT, Howard RM, Winkler M. Cell-free in vitro reduction of carboxylates to aldehydes: With crude enzyme preparations to a key pharmaceutical building block. Biotechnol J 2021; 16:e2000315. [PMID: 33245607 DOI: 10.1002/biot.202000315] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/03/2020] [Indexed: 11/07/2022]
Abstract
The scarcity of practical methods for aldehyde synthesis in chemistry necessitates the development of mild, selective procedures. Carboxylic acid reductases catalyze aldehyde formation from stable carboxylic acid precursors in an aqueous solution. Carboxylic acid reductases were employed to catalyze aldehyde formation in a cell-free system with activation energy and reducing equivalents provided through auxiliary proteins for ATP and NADPH recycling. In situ product removal was used to suppress over-reduction due to background enzyme activities, and an N-protected 4-formyl-piperidine pharma synthon was prepared in 61% isolated yield. This is the first report of preparative aldehyde synthesis with carboxylic acid reductases employing crude, commercially available enzyme preparations.
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Affiliation(s)
- Anna Schwarz
- Austrian Center of Industrial Biotechnology, Area Biotransformation, Graz, Austria
| | - Sebastian Hecko
- Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria
| | - Florian Rudroff
- Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria
| | - Jeffrey T Kohrt
- Pfizer Worldwide Research and Development, Applied Synthesis Technologies - Biocatalysis, Groton, USA
| | - Roger M Howard
- Pfizer Worldwide Research and Development, Applied Synthesis Technologies - Biocatalysis, Groton, USA
| | - Margit Winkler
- Austrian Center of Industrial Biotechnology, Area Biotransformation, Graz, Austria.,Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria
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61
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Hammer AK, Emrich NO, Ott J, Birk F, Fraatz MA, Ley JP, Geissler T, Bornscheuer UT, Zorn H. Biotechnological Production and Sensory Evaluation of ω1-Unsaturated Aldehydes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:345-353. [PMID: 33350305 DOI: 10.1021/acs.jafc.0c06872] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Lipid extracts of the fungus Flammulina velutipes were found to contain various scarce fatty acids including dodec-11-enoic acid and di- and tri-unsaturated C16 isomers. A biotechnological approach using a heterologously expressed carboxylic acid reductase was developed to transform the fatty acids into the respective aldehydes, yielding inter alia dodec-11-enal. Supplementation studies gave insights into the fungal biosynthesis of this rarely occurring acid and suggested a terminal desaturation of lauric acid being responsible for its formation. A systematic structure-odor relationship assessment of terminally unsaturated aldehydes (C7-C13) revealed odor thresholds in the range of 0.24-22 μg/L in aqueous solution and 0.039-29 ng/L in air. In both cases, non-8-enal was identified as the most potent compound. All aldehydes exhibited green odor qualities. Short-chained substances were additionally associated with grassy, melon-, and cucumber-like notes, while longer-chained homologs smelled soapy and coriander leaf-like with partly herbaceous nuances. Dodec-11-enal turned out to be of highly pleasant scent without off-notes.
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Affiliation(s)
- Andreas K Hammer
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, 35392 Giessen, Germany
| | - Nils O Emrich
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Janina Ott
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Florian Birk
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Marco A Fraatz
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, 35392 Giessen, Germany
| | - Jakob P Ley
- Symrise AG, Muehlenfeldstrasse 1, 37603 Holzminden, Germany
| | | | - Uwe T Bornscheuer
- Department of Biotechnology and Enzyme Catalysis, Greifswald University, Felix-Hausdorff-Strasse 4, 17487 Greifswald, Germany
| | - Holger Zorn
- Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, 35392 Giessen, Germany
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62
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Influence of Culture Conditions on the Bioreduction of Organic Acids to Alcohols by Thermoanaerobacter pseudoethanolicus. Microorganisms 2021; 9:microorganisms9010162. [PMID: 33445711 PMCID: PMC7828175 DOI: 10.3390/microorganisms9010162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Accepted: 01/08/2021] [Indexed: 11/17/2022] Open
Abstract
Thermoanaerobacter species have recently been observed to reduce carboxylic acids to their corresponding alcohols. The present investigation shows that Thermoanaerobacter pseudoethanolicus converts C2-C6 short-chain fatty acids (SCFAs) to their corresponding alcohols in the presence of glucose. The conversion yields varied from 21% of 3-methyl-1-butyrate to 57.9% of 1-pentanoate being converted to their corresponding alcohols. Slightly acidic culture conditions (pH 6.5) was optimal for the reduction. By increasing the initial glucose concentration, an increase in the conversion of SCFAs reduced to their corresponding alcohols was observed. Inhibitory experiments on C2-C8 alcohols showed that C4 and higher alcohols are inhibitory to T. pseudoethanolicus suggesting that other culture modes may be necessary to improve the amount of fatty acids reduced to the analogous alcohol. The reduction of SCFAs to their corresponding alcohols was further demonstrated using 13C-labelled fatty acids and the conversion was followed kinetically. Finally, increased activity of alcohol dehydrogenase (ADH) and aldehyde oxidation activity was observed in cultures of T. pseudoethanolicus grown on glucose as compared to glucose supplemented with either 3-methyl-1-butyrate or pentanoate, using both NADH and NADPH as cofactors, although the presence of the latter showed higher ADH and aldehyde oxidoreductase (ALDH) activity.
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63
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Krishnan A, McNeil BA, Stuart DT. Biosynthesis of Fatty Alcohols in Engineered Microbial Cell Factories: Advances and Limitations. Front Bioeng Biotechnol 2020; 8:610936. [PMID: 33344437 PMCID: PMC7744569 DOI: 10.3389/fbioe.2020.610936] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/10/2020] [Indexed: 11/19/2022] Open
Abstract
Concerns about climate change and environmental destruction have led to interest in technologies that can replace fossil fuels and petrochemicals with compounds derived from sustainable sources that have lower environmental impact. Fatty alcohols produced by chemical synthesis from ethylene or by chemical conversion of plant oils have a large range of industrial applications. These chemicals can be synthesized through biological routes but their free forms are produced in trace amounts naturally. This review focuses on how genetic engineering of endogenous fatty acid metabolism and heterologous expression of fatty alcohol producing enzymes have come together resulting in the current state of the field for production of fatty alcohols by microbial cell factories. We provide an overview of endogenous fatty acid synthesis, enzymatic methods of conversion to fatty alcohols and review the research to date on microbial fatty alcohol production. The primary focus is on work performed in the model microorganisms, Escherichia coli and Saccharomyces cerevisiae but advances made with cyanobacteria and oleaginous yeasts are also considered. The limitations to production of fatty alcohols by microbial cell factories are detailed along with consideration to potential research directions that may aid in achieving viable commercial scale production of fatty alcohols from renewable feedstock.
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Affiliation(s)
- Anagha Krishnan
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Bonnie A McNeil
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - David T Stuart
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
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64
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Insights into the unique carboxylation reactions in the metabolism of propylene and acetone. Biochem J 2020; 477:2027-2038. [PMID: 32497192 DOI: 10.1042/bcj20200174] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 01/16/2023]
Abstract
Alkenes and ketones are two classes of ubiquitous, toxic organic compounds in natural environments produced in several biological and anthropogenic processes. In spite of their toxicity, these compounds are utilized as primary carbon and energy sources or are generated as intermediate metabolites in the metabolism of other compounds by many diverse bacteria. The aerobic metabolism of some of the smallest and most volatile of these compounds (propylene, acetone, isopropanol) involves novel carboxylation reactions resulting in a common product acetoacetate. Propylene is metabolized in a four-step pathway involving five enzymes where the penultimate step is a carboxylation reaction catalyzed by a unique disulfide oxidoreductase that couples reductive cleavage of a thioether linkage with carboxylation to produce acetoacetate. The carboxylation of isopropanol begins with conversion to acetone via an alcohol dehydrogenase. Acetone is converted to acetoacetate in a single step by an acetone carboxylase which couples the hydrolysis of MgATP to the activation of both acetone and bicarbonate, generating highly reactive intermediates that are condensed into acetoacetate at a Mn2+ containing the active site. Acetoacetate is then utilized in central metabolism where it is readily converted to acetyl-coenzyme A and subsequently converted into biomass or utilized in energy metabolism via the tricarboxylic acid cycle. This review summarizes recent structural and biochemical findings that have contributed significant insights into the mechanism of these two unique carboxylating enzymes.
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65
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Sarak S, Sung S, Jeon H, Patil MD, Khobragade TP, Pagar AD, Dawson PE, Yun H. An Integrated Cofactor/Co‐Product Recycling Cascade for the Biosynthesis of Nylon Monomers from Cycloalkylamines. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202012658] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Sharad Sarak
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Sihyong Sung
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Hyunwoo Jeon
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Mahesh D. Patil
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Taresh P. Khobragade
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Amol D. Pagar
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
| | - Philip E. Dawson
- Department of Chemistry The Scripps Research Institute 10550 N. Torrey Pines Road La Jolla CA 92037 USA
| | - Hyungdon Yun
- Department of Systems Biotechnology Konkuk University 120 Neungdong-ro, Gwangjin-gu Seoul 050-29 South Korea
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66
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Basri RS, Rahman RNZRA, Kamarudin NHA, Ali MSM. Cyanobacterial aldehyde deformylating oxygenase: Structure, function, and potential in biofuels production. Int J Biol Macromol 2020; 164:3155-3162. [PMID: 32841666 DOI: 10.1016/j.ijbiomac.2020.08.162] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/04/2020] [Accepted: 08/20/2020] [Indexed: 11/27/2022]
Abstract
The conversion of aldehydes to valuable alkanes via cyanobacterial aldehyde deformylating oxygenase is of great interest. The availability of fossil reserves that keep on decreasing due to human exploitation is worrying, and even more troubling is the combustion emission from the fuel, which contributes to the environmental crisis and health issues. Hence, it is crucial to use a renewable and eco-friendly alternative that yields compound with the closest features as conventional petroleum-based fuel, and that can be used in biofuels production. Cyanobacterial aldehyde deformylating oxygenase (ADO) is a metal-dependent enzyme with an α-helical structure that contains di‑iron at the active site. The substrate enters the active site of every ADO through a hydrophobic channel. This enzyme exhibits catalytic activity toward converting Cn aldehyde to Cn-1 alkane and formate as a co-product. These cyanobacterial enzymes are small and easy to manipulate. Currently, ADOs are broadly studied and engineered for improving their enzymatic activity and substrate specificity for better alkane production. This review provides a summary of recent progress in the study of the structure and function of ADO, structural-based engineering of the enzyme, and highlight its potential in producing biofuels.
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Affiliation(s)
- Rose Syuhada Basri
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Raja Noor Zaliha Raja Abd Rahman
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Nor Hafizah Ahmad Kamarudin
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Centre of Foundation Studies for Agricultural Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Mohd Shukuri Mohamad Ali
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
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67
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Amer M, Toogood H, Scrutton NS. Engineering nature for gaseous hydrocarbon production. Microb Cell Fact 2020; 19:209. [PMID: 33187524 PMCID: PMC7661322 DOI: 10.1186/s12934-020-01470-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 11/04/2020] [Indexed: 11/10/2022] Open
Abstract
The development of sustainable routes to the bio-manufacture of gaseous hydrocarbons will contribute widely to future energy needs. Their realisation would contribute towards minimising over-reliance on fossil fuels, improving air quality, reducing carbon footprints and enhancing overall energy security. Alkane gases (propane, butane and isobutane) are efficient and clean-burning fuels. They are established globally within the transportation industry and are used for domestic heating and cooking, non-greenhouse gas refrigerants and as aerosol propellants. As no natural biosynthetic routes to short chain alkanes have been discovered, de novo pathways have been engineered. These pathways incorporate one of two enzymes, either aldehyde deformylating oxygenase or fatty acid photodecarboxylase, to catalyse the final step that leads to gas formation. These new pathways are derived from established routes of fatty acid biosynthesis, reverse β-oxidation for butanol production, valine biosynthesis and amino acid degradation. Single-step production of alkane gases in vivo is also possible, where one recombinant biocatalyst can catalyse gas formation from exogenously supplied short-chain fatty acid precursors. This review explores current progress in bio-alkane gas production, and highlights the potential for implementation of scalable and sustainable commercial bioproduction hubs.
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Affiliation(s)
- Mohamed Amer
- EPSRC/BBSRC Future Biomanufacturing Research Hub, Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, BBSRC/EPSRC, The University of Manchester, Manchester, M1 7DN, UK
| | - Helen Toogood
- EPSRC/BBSRC Future Biomanufacturing Research Hub, Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, BBSRC/EPSRC, The University of Manchester, Manchester, M1 7DN, UK
| | - Nigel S Scrutton
- EPSRC/BBSRC Future Biomanufacturing Research Hub, Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, BBSRC/EPSRC, The University of Manchester, Manchester, M1 7DN, UK.
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68
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Hollmann F, Opperman DJ, Paul CE. Biokatalytische Reduktionen aus der Sicht eines Chemikers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001876] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Frank Hollmann
- Department of Biotechnology Delft University of Technology Van der Maasweg 9 2629 HZ Delft Niederlande
- Department of Biotechnology University of the Free State 205 Nelson Mandela Drive Bloemfontein 9300 Südafrika
| | - Diederik J. Opperman
- Department of Biotechnology University of the Free State 205 Nelson Mandela Drive Bloemfontein 9300 Südafrika
| | - Caroline E. Paul
- Department of Biotechnology Delft University of Technology Van der Maasweg 9 2629 HZ Delft Niederlande
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69
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Foo JL, Rasouliha BH, Susanto AV, Leong SSJ, Chang MW. Engineering an Alcohol-Forming Fatty Acyl-CoA Reductase for Aldehyde and Hydrocarbon Biosynthesis in Saccharomyces cerevisiae. Front Bioeng Biotechnol 2020; 8:585935. [PMID: 33123518 PMCID: PMC7573125 DOI: 10.3389/fbioe.2020.585935] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/08/2020] [Indexed: 11/19/2022] Open
Abstract
Aldehydes are a class of highly versatile chemicals that can undergo a wide range of chemical reactions and are in high demand as starting materials for chemical manufacturing. Biologically, fatty aldehydes can be produced from fatty acyl-CoA by the action of fatty acyl-CoA reductases. The aldehydes produced can be further converted enzymatically to other valuable derivatives. Thus, metabolic engineering of microorganisms for biosynthesizing aldehydes and their derivatives could provide an economical and sustainable platform for key aldehyde precursor production and subsequent conversion to various value-added chemicals. Saccharomyces cerevisiae is an excellent host for this purpose because it is a robust organism that has been used extensively for industrial biochemical production. However, fatty acyl-CoA-dependent aldehyde-forming enzymes expressed in S. cerevisiae thus far have extremely low activities, hence limiting direct utilization of fatty acyl-CoA as substrate for aldehyde biosynthesis. Toward overcoming this challenge, we successfully engineered an alcohol-forming fatty acyl-CoA reductase for aldehyde production through rational design. We further improved aldehyde production through strain engineering by deleting competing pathways and increasing substrate availability. Subsequently, we demonstrated alkane and alkene production as one of the many possible applications of the aldehyde-producing strain. Overall, by protein engineering of a fatty acyl-CoA reductase to alter its activity and metabolic engineering of S. cerevisiae, we generated strains with the highest reported cytosolic aliphatic aldehyde and alkane/alkene production to date in S. cerevisiae from fatty acyl-CoA.
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Affiliation(s)
- Jee Loon Foo
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
| | - Bahareh Haji Rasouliha
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
| | - Adelia Vicanatalita Susanto
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
| | - Susanna Su Jan Leong
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore.,Singapore Institute of Technology, Singapore, Singapore
| | - Matthew Wook Chang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
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70
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Multi-strain volatile profiling of pathogenic and commensal cutaneous bacteria. Sci Rep 2020; 10:17971. [PMID: 33087843 PMCID: PMC7578783 DOI: 10.1038/s41598-020-74909-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/08/2020] [Indexed: 12/12/2022] Open
Abstract
The detection of volatile organic compounds (VOC) emitted by pathogenic bacteria has been proposed as a potential non-invasive approach for characterising various infectious diseases as well as wound infections. Studying microbial VOC profiles in vitro allows the mechanisms governing VOC production and the cellular origin of VOCs to be deduced. However, inter-study comparisons of microbial VOC data remains a challenge due to the variation in instrumental and growth parameters across studies. In this work, multiple strains of pathogenic and commensal cutaneous bacteria were analysed using headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry. A kinetic study was also carried out to assess the relationship between bacterial VOC profiles and the growth phase of cells. Comprehensive bacterial VOC profiles were successfully discriminated at the species-level, while strain-level variation was only observed in specific species and to a small degree. Temporal emission kinetics showed that the emission of particular compound groups were proportional to the respective growth phase for individual S. aureus and P. aeruginosa samples. Standardised experimental workflows are needed to improve comparability across studies and ultimately elevate the field of microbial VOC profiling. Our results build on and support previous literature and demonstrate that comprehensive discriminative results can be achieved using simple experimental and data analysis workflows.
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71
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Horvat M, Larch T, Rudroff F, Winkler M. Amino Benzamidoxime (ABAO)‐Based Assay to Identify Efficient Aldehyde‐Producing
Pichia pastoris
Clones. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
| | | | - Florian Rudroff
- Institute of Applied Synthetic Chemistry TU Wien Getreidemarkt 9/OC-163 1060 Vienna Austria
| | - Margit Winkler
- acib GmbH Krenngasse 37 8010 Graz Austria
- Institute of Molecular Biotechnology TU Graz Petersgasse 14 8010 Graz Austria
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72
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Jawed K, Abdelaal AS, Koffas MAG, Yazdani SS. Improved Butanol Production Using FASII Pathway in E. coli. ACS Synth Biol 2020; 9:2390-2398. [PMID: 32813973 DOI: 10.1021/acssynbio.0c00154] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
n-Butanol is often considered a potential substitute for gasoline due to its physicochemical properties being closely related to those of gasoline. In this study, we extend our earlier work to convert endogenously producing butyrate via the FASII pathway using thioesterase TesBT to its corresponding alcohol, i.e., butanol. We first assembled pathway genes, i.e., car encoding carboxylic acid reductase from Mycobacterium marinum, sfp encoding phosphopantetheinyl transferase from Bacillus subtilis, and adh2 encoding alcohol dehydrogenase from S. cerevisiae, responsible for bioconversion of butyrate to butanol in three different configurations (Operon, Pseudo-Operon, and Monocistronic) to achieve optimum expression of each gene and compared with the clostridial solventogenic pathway for in vivo conversion of butyrate to butanol under aerobic conditions. An E. coli strain harboring car, sfp, and adh2 in pseudo-operon configuration was able to convert butyrate to butanol with 100% bioconversion efficiency when supplemented with 1 g/L of butyrate. Further, co-cultivation of an upstream strain (butyrate-producing) with a downstream strain (butyrate to butanol converting) at different inoculation ratios was investigated, and an optimized ratio of 1:4 (upstream strain: downstream strain) was found to produce ∼2 g/L butanol under fed-batch fermentation. Further, a mono-cultivation approach was applied by transforming a plasmid harboring tesBT gene into the downstream strain. This approach produced 0.42 g/L in a test tube and ∼2.9 g/L butanol under fed-batch fermentation. This is the first report where both mono- and co-cultivation approaches were tested and compared for butanol production, and butanol titers achieved using both strategies are the highest reported values in recombinant E. coli utilizing FASII pathway.
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Affiliation(s)
- Kamran Jawed
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, 110067 New Delhi, India
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Ali Samy Abdelaal
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, 110067 New Delhi, India
- Department of Genetics, Faculty of Agriculture, Damietta University, 34511 Damietta, Egypt
| | - Mattheos A. G. Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, 110067 New Delhi, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, 110067 New Delhi, India
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73
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Engineering carboxylic acid reductase for selective synthesis of medium-chain fatty alcohols in yeast. Proc Natl Acad Sci U S A 2020; 117:22974-22983. [PMID: 32873649 DOI: 10.1073/pnas.2010521117] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Medium-chain fatty alcohols (MCFOHs, C6 to C12) are potential substitutes for fossil fuels, such as diesel and jet fuels, and have wide applications in various manufacturing processes. While today MCFOHs are mainly sourced from petrochemicals or plant oils, microbial biosynthesis represents a scalable, reliable, and sustainable alternative. Here, we aim to establish a Saccharomyces cerevisiae platform capable of selectively producing MCFOHs. This was enabled by tailoring the properties of a bacterial carboxylic acid reductase from Mycobacterium marinum (MmCAR). Extensive protein engineering, including directed evolution, structure-guided semirational design, and rational design, was implemented. MmCAR variants with enhanced activity were identified using a growth-coupled high-throughput screening assay relying on the detoxification of the enzyme's substrate, medium-chain fatty acids (MCFAs). Detailed characterization demonstrated that both the specificity and catalytic activity of MmCAR was successfully improved and a yeast strain harboring the best MmCAR variant generated 2.8-fold more MCFOHs than the strain expressing the unmodified enzyme. Through deletion of the native MCFA exporter gene TPO1, MCFOH production was further improved, resulting in a titer of 252 mg/L for the final strain, which represents a significant improvement in MCFOH production in minimal medium by S. cerevisiae.
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74
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Horvat M, Winkler M. In Vivo
Reduction of Medium‐ to Long‐Chain Fatty Acids by Carboxylic Acid Reductase (CAR) Enzymes: Limitations and Solutions. ChemCatChem 2020. [DOI: 10.1002/cctc.202000895] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Melissa Horvat
- acib –Austrian Center of Industrial Biotechnology Krenngasse 37 8010 Graz Austria
| | - Margit Winkler
- acib –Austrian Center of Industrial Biotechnology Krenngasse 37 8010 Graz Austria
- Institute of Molecular Biotechnology Graz University of Technology Petersgasse 14 8010 Graz Austria
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75
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Bacterial synthesis of C3-C5 diols via extending amino acid catabolism. Proc Natl Acad Sci U S A 2020; 117:19159-19167. [PMID: 32719126 DOI: 10.1073/pnas.2003032117] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Amino acids are naturally occurring and structurally diverse metabolites in biological system, whose potentials for chemical expansion, however, have not been fully explored. Here, we devise a metabolic platform capable of producing industrially important C3-C5 diols from amino acids. The presented platform combines the natural catabolism of charged amino acids with a catalytically efficient and thermodynamically favorable diol formation pathway, created by expanding the substrate scope of the carboxylic acid reductase toward noncognate ω-hydroxylic acids. Using the established platform as gateways, seven different diol-convertible amino acids are converted to diols including 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol. Particularly, we afford to optimize the production of 1,4-butanediol and demonstrate the de novo production of 1,5-pentanediol from glucose, with titers reaching 1.41 and 0.97 g l-1, respectively. Our work presents a metabolic platform that enriches the pathway repertoire for nonnatural diols with feedstock flexibility to both sugar and protein hydrolysates.
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76
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Kramer L, Le X, Rodriguez M, Wilson MA, Guo J, Niu W. Engineering Carboxylic Acid Reductase (CAR) through a Whole-Cell Growth-Coupled NADPH Recycling Strategy. ACS Synth Biol 2020; 9:1632-1637. [PMID: 32589835 DOI: 10.1021/acssynbio.0c00290] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Rapid evolution of enzyme activities is often hindered by the lack of efficient and affordable methods to identify beneficial mutants. We report the development of a new growth-coupled selection method for evolving NADPH-consuming enzymes based on the recycling of this redox cofactor. The method relies on a genetically modified Escherichia coli strain, which overaccumulates NADPH. This method was applied to the engineering of a carboxylic acid reductase (CAR) for improved catalytic activities on 2-methoxybenzoate and adipate. Mutant enzymes with up to 17-fold improvement in catalytic efficiency were identified from single-site saturated mutagenesis libraries. Obtained mutants were successfully applied to whole-cell conversions of adipate into 1,6-hexanediol, a C6 monomer commonly used in polymer industry.
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Affiliation(s)
- Levi Kramer
- Department of Chemical & Biomolecular Engineering, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Xuan Le
- Department of Chemical & Biomolecular Engineering, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Marisa Rodriguez
- Department of Chemical & Biomolecular Engineering, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Mark A. Wilson
- Department of Biochemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Jiantao Guo
- Department of Chemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Wei Niu
- Department of Chemical & Biomolecular Engineering, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
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77
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Dutta S. Hydro(deoxygenation) Reaction Network of Lignocellulosic Oxygenates. CHEMSUSCHEM 2020; 13:2894-2915. [PMID: 32134557 DOI: 10.1002/cssc.202000247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/27/2020] [Indexed: 06/10/2023]
Abstract
Hydrodeoxygenation (HDO) is a key transformation step to convert lignocellulosic oxygenates into drop-in and functional high-value hydrocarbons through controlled oxygen removal. Nevertheless, the mechanistic insights of HDO chemistry have been scarcely investigated as opposed to a significant extent of hydrodesulfurization chemistry. Current requirements emphasize certain underexplored events of HDO of oxygenates, which include 1) interactions of oxygenates of varied molecular size with active sites of the catalysts, 2) determining the conformation of oxygenates on the active site at the point of interaction, and 3) effects of oxygen contents of oxygenates on the reaction rate of HDO. It is realized that the molecular interactions of oxygenates with the surface of the catalyst dominates the degree and nature of deoxygenation to derive products with desired selectivity by overcoming complex separation processes in a biorefinery. Those oxygenates with high carbon numbers (>C10), multiple furan rings, and branched architectures are even more complex to understand. This article aims to focus on concise mechanistic analysis of biorefinery oxygenates (C10-35 ) for their deoxygenation processes, with a special emphasis on their interactions with active sites in a complex chemical environment. This article also addresses differentiation of the mode of interactions based on the molecular size of oxygenates. Deoxygenation processes coupled with or without ring opening of furan-based oxygenates and site-substrate cooperativity dictate the formation of diverse value-added products. Oxygen removal has been the key step for microbial deoxygenation by the use of oxygen-removing decarbonylase enzymes. However, challenges to obtain branched and long-chain hydrocarbons remain, which require special attention, including the invention of newer techniques to upgrade the process for combined depolymerization-HDO from real biomass.
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Affiliation(s)
- Saikat Dutta
- Molecular Catalysis & Energy (MCR) Laboratory, Amity Institute Click Chemistry Research & Studies (AICCRS), Amity University, Sector 125, Noida, 201303, India
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78
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Bioaldehydes and beyond: Expanding the realm of bioderived chemicals using biogenic aldehydes as platforms. Curr Opin Chem Biol 2020; 59:37-46. [PMID: 32454426 DOI: 10.1016/j.cbpa.2020.04.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/04/2020] [Accepted: 04/12/2020] [Indexed: 01/06/2023]
Abstract
Biofuels and biochemicals derived from renewable resources are sconsidered as potential solutions for the energy crisis and associated environmental problems that human beings are facing today. However, so far the available types of bioderived chemicals are rather limited, and production efficiency is generally low. Expanding the realm of bioderived chemicals and relevant derivatives can help motivate the development of bioenergy and the general bioeconomy. Aldehydes, possessing unique reactivity, hold great promise as platform chemicals for producing a large portfolio of bioproducts. In this review, we focus on production of aldehydes from renewable bioresources and derivatization of aldehydes through chemocatalysis, biocatalysis, or de novo biosynthesis. Perspectives on combining protein engineering and cascade reactions for advanced aldehyde derivatization are also provided.
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79
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Hu Y, Zhu Z, Nielsen J, Siewers V. Engineering Saccharomyces cerevisiae cells for production of fatty acid-derived biofuels and chemicals. Open Biol 2020; 9:190049. [PMID: 31088249 PMCID: PMC6544985 DOI: 10.1098/rsob.190049] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The yeast Saccharomyces cerevisiae is a widely used cell factory for the production of fuels and chemicals, in particular ethanol, a biofuel produced in large quantities. With a need for high-energy-density fuels for jets and heavy trucks, there is, however, much interest in the biobased production of hydrocarbons that can be derived from fatty acids. Fatty acids also serve as precursors to a number of oleochemicals and hence provide interesting platform chemicals. Here, we review the recent strategies applied to metabolic engineering of S. cerevisiae for the production of fatty acid-derived biofuels and for improvement of the titre, rate and yield (TRY). This includes, for instance, redirection of the flux towards fatty acids through engineering of the central carbon metabolism, balancing the redox power and varying the chain length of fatty acids by enzyme engineering. We also discuss the challenges that currently hinder further TRY improvements and the potential solutions in order to meet the requirements for commercial application.
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Affiliation(s)
- Yating Hu
- 1 Department of Biology and Biological Engineering, Chalmers University of Technology , 41296 Gothenburg , Sweden.,2 Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Zhiwei Zhu
- 1 Department of Biology and Biological Engineering, Chalmers University of Technology , 41296 Gothenburg , Sweden.,2 Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Jens Nielsen
- 1 Department of Biology and Biological Engineering, Chalmers University of Technology , 41296 Gothenburg , Sweden.,2 Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology , 41296 Gothenburg , Sweden.,3 Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , 2800 Kgs Lyngby , Denmark.,4 BioInnovation Institute , Ole Måløes Vej, 2200 Copenhagen N , Denmark
| | - Verena Siewers
- 1 Department of Biology and Biological Engineering, Chalmers University of Technology , 41296 Gothenburg , Sweden.,2 Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology , 41296 Gothenburg , Sweden
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80
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Enzymatic Synthesis of Aliphatic Primary ω-Amino Alcohols from ω-Amino Fatty Acids by Carboxylic Acid Reductase. Catal Letters 2020. [DOI: 10.1007/s10562-020-03233-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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81
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Shakeel T, Fatma Z, Yazdani SS. In vivo Quantification of Alkanes in Escherichia coli. Bio Protoc 2020; 10:e3593. [PMID: 33659559 DOI: 10.21769/bioprotoc.3593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/11/2020] [Accepted: 02/12/2020] [Indexed: 11/02/2022] Open
Abstract
Microbial production of alkanes employing synthetic biology tools has gained tremendous attention owing to the high energy density and similarity of alkanes to existing petroleum fuels. One of the most commonly studied pathways includes the production of alkanes by AAR (acyl-ACP (acyl carrier protein) reductase)-ADO (aldehyde deformylating oxygenase) pathway. Here, the intermediates of fatty acid synthesis pathway are used as substrate by the AAR enzyme to make fatty aldehyde, which is then deformylated by ADO to make linear chain alkane. However, the variation in substrate availability to the first enzyme of the pathway, i.e., AAR, via fatty acid synthesis pathway and low turnover of the ADO enzyme make calculation of yields and titers under in vivo conditions extremely difficult. In vivo assay employing external addition of defined substrates for ADO enzyme into the medium helps to monitor the influx of substrate hence providing a more accurate measurement of the product yields. In this protocol, we include a detailed guide for implementing the in vivo assay for monitoring alkane production in E. coli.
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Affiliation(s)
- Tabinda Shakeel
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.,DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Zia Fatma
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.,DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.,DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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82
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Structural insights into catalytic mechanism and product delivery of cyanobacterial acyl-acyl carrier protein reductase. Nat Commun 2020; 11:1525. [PMID: 32251275 PMCID: PMC7089970 DOI: 10.1038/s41467-020-15268-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 02/28/2020] [Indexed: 11/10/2022] Open
Abstract
Long-chain alk(a/e)nes represent the major constituents of conventional transportation fuels. Biosynthesis of alkanes is ubiquitous in many kinds of organisms. Cyanobacteria possess two enzymes, acyl-acyl carrier protein (acyl-ACP) reductase (AAR) and aldehyde-deformylating oxygenase (ADO), which function in a two-step alkane biosynthesis pathway. These two enzymes act in series and possibly form a complex that efficiently converts long chain fatty acyl-ACP/fatty acyl-CoA into hydrocarbon. While the structure of ADO has been previously described, structures of both AAR and AAR–ADO complex have not been solved, preventing deeper understanding of this pathway. Here, we report a ligand-free AAR structure, and three AAR–ADO complex structures in which AARs bind various ligands. Our results reveal the binding pattern of AAR with its substrate/cofactor, and suggest a potential aldehyde-transferring channel from AAR to ADO. Based on our structural and biochemical data, we proposed a model for the complete catalytic cycle of AAR. Acyl-acyl carrier protein reductase (AAR) and aldehyde deformylating oxygenase (ADO) are the two enzymes in a cyanobacterial alkane biosynthesis pathway that is of interest for biofuel production. Here the authors provide insights into the catalytic mechanisms of AAR and the coupling between the two enzymes by determining the crystal structures of AAR alone and three AAR–ADO complexes with various bound ligands.
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83
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Building cell factories for the production of advanced fuels. Biochem Soc Trans 2020; 47:1701-1714. [PMID: 31803925 DOI: 10.1042/bst20190168] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 12/31/2022]
Abstract
Synthetic biology-based engineering strategies are being extensively employed for microbial production of advanced fuels. Advanced fuels, being comparable in energy efficiency and properties to conventional fuels, have been increasingly explored as they can be directly incorporated into the current fuel infrastructure without the need for reconstructing the pre-existing set-up rendering them economically viable. Multiple metabolic engineering approaches have been used for rewiring microbes to improve existing or develop newly programmed cells capable of efficient fuel production. The primary challenge in using these approaches is improving the product yield for the feasibility of the commercial processes. Some of the common roadblocks towards enhanced fuel production include - limited availability of flux towards precursors and desired pathways due to presence of competing pathways, limited cofactor and energy supply in cells, the low catalytic activity of pathway enzymes, obstructed product transport, and poor tolerance of host cells for end products. Consequently, despite extensive studies on the engineering of microbial hosts, the costs of industrial-scale production of most of these heterologously produced fuel compounds are still too high. Though considerable progress has been made towards successfully producing some of these biofuels, a substantial amount of work needs to be done for improving the titers of others. In this review, we have summarized the different engineering strategies that have been successfully used for engineering pathways into commercial hosts for the production of advanced fuels and different approaches implemented for tuning host strains and pathway enzymes for scaling up production levels.
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84
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Wichmann J, Lauersen KJ, Kruse O. Green algal hydrocarbon metabolism is an exceptional source of sustainable chemicals. Curr Opin Biotechnol 2020; 61:28-37. [DOI: 10.1016/j.copbio.2019.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 09/25/2019] [Indexed: 10/25/2022]
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85
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Using enzyme cascades in biocatalysis: Highlight on transaminases and carboxylic acid reductases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140322. [DOI: 10.1016/j.bbapap.2019.140322] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/07/2019] [Accepted: 11/08/2019] [Indexed: 12/21/2022]
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86
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Jaroensuk J, Intasian P, Wattanasuepsin W, Akeratchatapan N, Kesornpun C, Kittipanukul N, Chaiyen P. Enzymatic reactions and pathway engineering for the production of renewable hydrocarbons. J Biotechnol 2020; 309:1-19. [DOI: 10.1016/j.jbiotec.2019.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 12/14/2019] [Accepted: 12/15/2019] [Indexed: 01/23/2023]
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87
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Sulzbach M, Kunjapur AM. The Pathway Less Traveled: Engineering Biosynthesis of Nonstandard Functional Groups. Trends Biotechnol 2020; 38:532-545. [PMID: 31954529 DOI: 10.1016/j.tibtech.2019.12.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 12/12/2022]
Abstract
The field of metabolic engineering has achieved biochemical routes for conversion of renewable inputs to structurally diverse chemicals, but these products contain a limited number of chemical functional groups. In this review, we provide an overview of the progression of uncommon or 'nonstandard' functional groups from the elucidation of their biosynthetic machinery to the pathway optimization framework of metabolic engineering. We highlight exemplary efforts from primarily the last 5 years for biosynthesis of aldehyde, ester, terminal alkyne, terminal alkene, fluoro, epoxide, nitro, nitroso, nitrile, and hydrazine functional groups. These representative nonstandard functional groups vary in development stage and showcase the pipeline of chemical diversity that could soon appear within customized, biologically produced molecules.
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Affiliation(s)
- Morgan Sulzbach
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19711, USA
| | - Aditya M Kunjapur
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19711, USA.
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88
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Fedorchuk TP, Khusnutdinova AN, Evdokimova E, Flick R, Di Leo R, Stogios P, Savchenko A, Yakunin AF. One-Pot Biocatalytic Transformation of Adipic Acid to 6-Aminocaproic Acid and 1,6-Hexamethylenediamine Using Carboxylic Acid Reductases and Transaminases. J Am Chem Soc 2020; 142:1038-1048. [PMID: 31886667 DOI: 10.1021/jacs.9b11761] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Production of platform chemicals from renewable feedstocks is becoming increasingly important due to concerns on environmental contamination, climate change, and depletion of fossil fuels. Adipic acid (AA), 6-aminocaproic acid (6-ACA) and 1,6-hexamethylenediamine (HMD) are key precursors for nylon synthesis, which are currently produced primarily from petroleum-based feedstocks. In recent years, the biosynthesis of adipic acid from renewable feedstocks has been demonstrated using both bacterial and yeast cells. Here we report the biocatalytic conversion/transformation of AA to 6-ACA and HMD by carboxylic acid reductases (CARs) and transaminases (TAs), which involves two rounds (cascades) of reduction/amination reactions (AA → 6-ACA → HMD). Using purified wild type CARs and TAs supplemented with cofactor regenerating systems for ATP, NADPH, and amine donor, we established a one-pot enzyme cascade catalyzing up to 95% conversion of AA to 6-ACA. To increase the cascade activity for the transformation of 6-ACA to HMD, we determined the crystal structure of the CAR substrate-binding domain in complex with AMP and succinate and engineered three mutant CARs with enhanced activity against 6-ACA. In combination with TAs, the CAR L342E protein showed 50-75% conversion of 6-ACA to HMD. For the transformation of AA to HMD (via 6-ACA), the wild type CAR was combined with the L342E variant and two different TAs resulting in up to 30% conversion to HMD and 70% to 6-ACA. Our results highlight the suitability of CARs and TAs for several rounds of reduction/amination reactions in one-pot cascade systems and their potential for the biobased synthesis of terminal amines.
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Affiliation(s)
- Tatiana P Fedorchuk
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada.,Institute of Basic Biological Problems , Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Anna N Khusnutdinova
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada.,Institute of Basic Biological Problems , Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Elena Evdokimova
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada
| | - Robert Flick
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada
| | - Rosa Di Leo
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada
| | - Peter Stogios
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada
| | - Alexei Savchenko
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada.,Department of Microbiology, Immunology and Infectious Diseases , University of Calgary , Calgary , Alberta T2N 4N1 , Canada
| | - Alexander F Yakunin
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada.,Centre for Environmental Biotechnology, School of Natural Sciences , Bangor University , Gwynedd LL57 2UW , U.K
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89
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Jiang Y, Li Z, Zheng S, Xu H, Zhou YJ, Gao Z, Meng C, Li S. Establishing an enzyme cascade for one-pot production of α-olefins from low-cost triglycerides and oils without exogenous H 2O 2 addition. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:52. [PMID: 32190117 PMCID: PMC7075034 DOI: 10.1186/s13068-020-01684-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 02/21/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND Biological α-olefins can be used as both biofuels and high value-added chemical precursors to lubricants, polymers, and detergents. The prototypic CYP152 peroxygenase family member OleTJE from Jeotgalicoccus sp. ATCC 8456 catalyzes a single-step decarboxylation of free fatty acids (FFAs) to form α-olefins using H2O2 as a cofactor, thus attracting much attention since its discovery. To improve the productivity of α-olefins, significant efforts on protein engineering, electron donor engineering, and metabolic engineering of OleTJE have been made. However, little success has been achieved in obtaining α-olefin high-producer microorganisms due to multiple reasons such as the tight regulation of FFA biosynthesis, the difficulty of manipulating multi-enzyme metabolic network, and the poor catalytic performance of OleTJE. RESULTS In this study, a novel enzyme cascade was developed for one-pot production of α-olefins from low-cost triacylglycerols (TAGs) and natural oils without exogenous H2O2 addition. This artificial biocatalytic route consists of a lipase (CRL, AOL or Lip2) for TAG hydrolysis to produce glycerol and free fatty acids (FFAs), an alditol oxidase (AldO) for H2O2 generation upon glycerol oxidation, and the P450 fatty acid decarboxylase OleTJE for FFA decarboxylation using H2O2 generated in situ. The multi-enzyme system was systematically optimized leading to the production of α-olefins with the conversion rates ranging from 37.2 to 68.5%. Furthermore, a reaction using lyophilized CRL/OleTJE/AldO enzymes at an optimized ratio (5 U/6 μM/30 μM) gave a promising α-olefin yield of 0.53 g/L from 1500 μM (~1 g/L) coconut oil. CONCLUSIONS The one-pot enzyme cascade was successfully established and applied to prepare high value-added α-olefins from low-cost and renewable TAGs/natural oils. This system is independent of exogenous addition of H2O2, thus not only circumventing the detrimental effect of H2O2 on the stability and activity of involved enzymes, but also lower the overall costs on the TAG-to-olefin transformation. It is anticipated that this biotransformation system will become industrially relevant in the future upon more engineering efforts based on this proof-of-concept work.
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Affiliation(s)
- Yuanyuan Jiang
- Shandong Provincial Key Laboratory of Synthetic Biology, CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Zhong Li
- Shandong Provincial Key Laboratory of Synthetic Biology, CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Shanmin Zheng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237 Shandong China
- School of Life Sciences, Shandong University of Technology, Zibo, 255000 Shandong China
| | - Huifang Xu
- Shandong Provincial Key Laboratory of Synthetic Biology, CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Yongjin J. Zhou
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 Liaoning China
| | - Zhengquan Gao
- School of Life Sciences, Shandong University of Technology, Zibo, 255000 Shandong China
| | - Chunxiao Meng
- School of Life Sciences, Shandong University of Technology, Zibo, 255000 Shandong China
| | - Shengying Li
- Shandong Provincial Key Laboratory of Synthetic Biology, CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237 Shandong China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 Shandong China
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90
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Carboxylic acid reductases in metabolic engineering. J Biotechnol 2020; 307:1-14. [DOI: 10.1016/j.jbiotec.2019.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/30/2019] [Accepted: 10/01/2019] [Indexed: 01/29/2023]
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91
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Calcagnile M, Tredici SM, Talà A, Alifano P. Bacterial Semiochemicals and Transkingdom Interactions with Insects and Plants. INSECTS 2019; 10:E441. [PMID: 31817999 PMCID: PMC6955855 DOI: 10.3390/insects10120441] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/02/2019] [Accepted: 12/05/2019] [Indexed: 01/08/2023]
Abstract
A peculiar feature of all living beings is their capability to communicate. With the discovery of the quorum sensing phenomenon in bioluminescent bacteria in the late 1960s, it became clear that intraspecies and interspecies communications and social behaviors also occur in simple microorganisms such as bacteria. However, at that time, it was difficult to imagine how such small organisms-invisible to the naked eye-could influence the behavior and wellbeing of the larger, more complex and visible organisms they colonize. Now that we know this information, the challenge is to identify the myriad of bacterial chemical signals and communication networks that regulate the life of what can be defined, in a whole, as a meta-organism. In this review, we described the transkingdom crosstalk between bacteria, insects, and plants from an ecological perspective, providing some paradigmatic examples. Second, we reviewed what is known about the genetic and biochemical bases of the bacterial chemical communication with other organisms and how explore the semiochemical potential of a bacterium can be explored. Finally, we illustrated how bacterial semiochemicals managing the transkingdom communication may be exploited from a biotechnological point of view.
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Affiliation(s)
| | | | | | - Pietro Alifano
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy; (M.C.); (S.M.T.); (A.T.)
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92
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Thomas A, Cutlan R, Finnigan W, van der Giezen M, Harmer N. Highly thermostable carboxylic acid reductases generated by ancestral sequence reconstruction. Commun Biol 2019; 2:429. [PMID: 31799431 PMCID: PMC6874671 DOI: 10.1038/s42003-019-0677-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/04/2019] [Indexed: 12/19/2022] Open
Abstract
Carboxylic acid reductases (CARs) are biocatalysts of industrial importance. Their properties, especially their poor stability, render them sub-optimal for use in a bioindustrial pipeline. Here, we employed ancestral sequence reconstruction (ASR) - a burgeoning engineering tool that can identify stabilizing but enzymatically neutral mutations throughout a protein. We used a three-algorithm approach to reconstruct functional ancestors of the Mycobacterial and Nocardial CAR1 orthologues. Ancestral CARs (AncCARs) were confirmed to be CAR enzymes with a preference for aromatic carboxylic acids. Ancestors also showed varied tolerances to solvents, pH and in vivo-like salt concentrations. Compared to well-studied extant CARs, AncCARs had a Tm up to 35 °C higher, with half-lives up to nine times longer than the greatest previously observed. Using ancestral reconstruction we have expanded the existing CAR toolbox with three new thermostable CAR enzymes, providing access to the high temperature biosynthesis of aldehydes to drive new applications in biocatalysis.
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Affiliation(s)
- Adam Thomas
- Living Systems Institute, Stocker Road, Exeter, EX4 4QD UK
- Present Address: Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD UK
| | - Rhys Cutlan
- Living Systems Institute, Stocker Road, Exeter, EX4 4QD UK
- Present Address: Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD UK
| | - William Finnigan
- Present Address: Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD UK
| | - Mark van der Giezen
- Present Address: Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD UK
- Centre for Organelle Research, University of Stavanger, Richard Johnsens gate 4, Stavanger, 4021 Norway
| | - Nicholas Harmer
- Living Systems Institute, Stocker Road, Exeter, EX4 4QD UK
- Present Address: Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD UK
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93
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Carboxylic acid reductase: Structure and mechanism. J Biotechnol 2019; 307:107-113. [PMID: 31689469 DOI: 10.1016/j.jbiotec.2019.10.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 11/22/2022]
Abstract
Carboxylic acid reductase (CAR) enzymes are large multi-domain proteins that catalyse the ATP- and NADPH-dependent reduction of wide range of acids to the corresponding aldehydes. This particular reaction is of considerable biotechnological interest. Recent advances in the structural and solution studies of isolated domain, di-domain and full-length CAR enzymes revealed valuable insights into the mechanism of carboxylic acid reduction activity. This review features the phylogenetic, sequence and structural insight into the CAR and implications of these observations in order to improve carboxylic acid reduction activity to develop CAR as robust biocatalyst.
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94
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Kruis AJ, Bohnenkamp AC, Patinios C, van Nuland YM, Levisson M, Mars AE, van den Berg C, Kengen SW, Weusthuis RA. Microbial production of short and medium chain esters: Enzymes, pathways, and applications. Biotechnol Adv 2019; 37:107407. [DOI: 10.1016/j.biotechadv.2019.06.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 05/24/2019] [Accepted: 06/09/2019] [Indexed: 12/12/2022]
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95
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Co-factor demand and regeneration in the enzymatic one-step reduction of carboxylates to aldehydes in cell-free systems. J Biotechnol 2019; 307:202-207. [PMID: 31672531 DOI: 10.1016/j.jbiotec.2019.10.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 10/24/2019] [Accepted: 10/24/2019] [Indexed: 11/20/2022]
Abstract
Addressing the challenges associated with the development of in vitro biocatalytic carboxylate reductions for potential applications, important aspects of the co-factor regeneration systems and strategies for minimizing over-reduction were investigated. The ATP recycling can be performed with similarly high efficiency exploiting the polyphosphate source by combining Meiothermus ruber polyphosphate kinase and adenylate kinase or with Sinorhizobium meliloti polyphosphate kinase instead of the latter. Carboxylate reductions with the enzyme candidates used in this work allow operating at co-factor concentrations of adenosine 5'-triphosphate and β-nicotinamide adenine dinucleotide 2'-phosphate of 100 μM and, thereby, reducing the amounts of alcohols formed by side activities in the enzyme preparations. This study confirmed the expected benefits of carboxylic acid reductases in chemoselectively reducing the carboxylates to the corresponding aldehydes while leaving reductively-sensitive nitro, ester and cyano groups intact.
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96
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Derrington SR, Turner NJ, France SP. Carboxylic acid reductases (CARs): An industrial perspective. J Biotechnol 2019; 304:78-88. [DOI: 10.1016/j.jbiotec.2019.08.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/14/2019] [Accepted: 08/14/2019] [Indexed: 01/09/2023]
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97
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Kramer L, Le X, Hankore ED, Wilson MA, Guo J, Niu W. Engineering and characterization of hybrid carboxylic acid reductases. J Biotechnol 2019; 304:52-56. [DOI: 10.1016/j.jbiotec.2019.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 02/04/2023]
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98
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Qu G, Liu B, Zhang K, Jiang Y, Guo J, Wang R, Miao Y, Zhai C, Sun Z. Computer-assisted engineering of the catalytic activity of a carboxylic acid reductase. J Biotechnol 2019; 306:97-104. [PMID: 31550488 DOI: 10.1016/j.jbiotec.2019.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 12/17/2022]
Abstract
Carboxylic acid reductases (CARs) play crucial roles in the biosynthesis of optically pure aldehydes with no side products. It has inspired synthetic organic chemists and biotechnologists to exploit them as catalysts in practical applications. However, levels of activity and substrate specificity are not routinely sufficient. Recent developments in protein engineering have produced numerous biocatalysts with new catalytic properties, whereas such efforts in CARs are limited. In this study, we show that the exploitation of information derived from catalytic mechanism analysis and molecular dynamics simulations assisted the semi-rational engineering of a CAR from Segniliparus rugosus (SrCAR) with the aim of increasing activity. Guided by protein-ligand interaction fingerprinting analysis, 17 residues at the substrate binding pockets were first identified. We then performed single site saturation mutagenesis and successfully obtained variants that gave high activities using benzoic acid as the model substrate. As a result, the best mutant K524W enabled 99% conversion and 17.28 s-1 mM-1kcat/Km, with 7- and 2-fold improvement compared to the wild-type, respectively. The engineered catalyst K524W as well as a second variant K524Q proved to be effective in the reduction of other benzoic acid derivatives. Insight into the source of enhanced activity was gained by molecular dynamics simulations.
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Affiliation(s)
- Ge Qu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Beibei Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Kun Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Yingying Jiang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Jinggong Guo
- State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, 85 Minglun Street, Kaifeng, 475001, China
| | - Ran Wang
- Zhengzhou Tabacco Research Institute of CNTC, No. 2 Fengyang Street, Zhengzhou, 450001, Henan, China
| | - Yuchen Miao
- State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, 85 Minglun Street, Kaifeng, 475001, China
| | - Chao Zhai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, 368 Youyi Road, Wuchang Wuhan, 430062, China
| | - Zhoutong Sun
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China.
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Fedorchuk TP, Khusnutdinova AN, Flick R, Yakunin AF. Site-directed mutagenesis and stability of the carboxylic acid reductase MAB4714 from Mycobacterium abscessus. J Biotechnol 2019; 303:72-79. [DOI: 10.1016/j.jbiotec.2019.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 11/30/2022]
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Horvat M, Fritsche S, Kourist R, Winkler M. Characterization of Type IV Carboxylate Reductases (CARs) for Whole Cell-Mediated Preparation of 3-Hydroxytyrosol. ChemCatChem 2019; 11:4171-4181. [PMID: 31681448 PMCID: PMC6813634 DOI: 10.1002/cctc.201900333] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/18/2019] [Indexed: 11/18/2022]
Abstract
Fragrance and flavor industries could not imagine business without aldehydes. Processes for their commercial production raise environmental and ecological concerns. The chemical reduction of organic acids to aldehydes is challenging. To fulfill the demand of a mild and selective reduction of carboxylic acids to aldehydes, carboxylic acid reductases (CARs) are gaining importance. We identified two new subtype IV fungal CARs from Dichomitus squalens CAR (DsCAR) and Trametes versicolor CAR (Tv2CAR) in addition to literature known Trametes versicolor CAR (TvCAR). Expression levels were improved by the co-expression of GroEL-GroES with either the trigger factor or the DnaJ-DnaK-GrpE system. Investigation of the substrate scope of the three enzymes revealed overlapping substrate-specificities. Tv2CAR and DsCAR showed a preferred pH range of 7.0 to 8.0 in bicine buffer. TvCAR showed highest activity at pH 6.5 to 7.5 in MES buffer and slightly reduced activity at pH 6.0 or 8.0. TvCAR appeared to tolerate a wider pH range without significant loss of activity. Type IV fungal CARs optimal temperature was in the range of 25-35 °C. TvCAR showed a melting temperature (Tm) of 55 °C indicating higher stability compared to type III and the other type IV fungal CARs (Tm 51-52 °C). Finally, TvCAR was used as the key enzyme for the bioreduction of 3,4-dihydroxyphenylacetic acid to the antioxidant 3-hydroxytyrosol (3-HT) and gave 58 mM of 3-HT after 24 h, which correlates to a productivity of 0.37 g L-1 h-1.
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Affiliation(s)
- Melissa Horvat
- acib – Austrian Center of Industrial BiotechnologyPetersgasse 148010GrazAustria
| | - Susanne Fritsche
- acib – Austrian Center of Industrial BiotechnologyPetersgasse 148010GrazAustria
| | - Robert Kourist
- Institute of Molecular BiotechnologyGraz University of TechnologyPetersgasse 148010GrazAustria
| | - Margit Winkler
- acib – Austrian Center of Industrial BiotechnologyPetersgasse 148010GrazAustria
- Institute of Molecular BiotechnologyGraz University of TechnologyPetersgasse 148010GrazAustria
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